Name:         PGSVP

Purpose:      set viewport (normalized device coordinates)

Category:     GRAPHICS

File:         pgplot.src

Author:       T.J. Pearson

Use:          see description below.

Description:

            SUBROUTINE PGSVP (XLEFT, XRIGHT, YBOT, YTOP)
            REAL XLEFT, XRIGHT, YBOT, YTOP
      
       Change the size and position of the viewport, specifying
       the viewport in normalized device coordinates.  Normalized
       device coordinates run from 0 to 1 in each dimension. The
       viewport is the rectangle on the view surface "through"
       which one views the graph.  All the PG routines which plot lines
       etc. plot them within the viewport, and lines are truncated at
       the edge of the viewport (except for axes, labels etc drawn with
       PGBOX or PGLAB).  The region of world space (the coordinate
       space of the graph) which is visible through the viewport is
       specified by a call to PGSWIN.  It is legal to request a
       viewport larger than the view surface; only the part which
       appears on the view surface will be plotted.
      
       Arguments:
        XLEFT  (input)  : x-coordinate of left hand edge of viewport, in NDC.
        XRIGHT (input)  : x-coordinate of right hand edge of viewport,
                          in NDC.
        YBOT   (input)  : y-coordinate of bottom edge of viewport, in NDC.
        YTOP   (input)  : y-coordinate of top  edge of viewport, in NDC.

Updates:      Oct 16, 1998: JPT automatically extracted from source.